高产纤维素酶里氏木霉菌株诱变选育及其发酵条件优化

Mutagenesis Breeding and Fermentation Condition Optimization of High Yield Cellulase Enzyme of Trichoderma Reesei

试验旨在研究高产纤维素酶里氏木霉诱变选育与发酵条件优化。采用常压室温等离子体(ARTP)诱变法处理里氏木霉,获得产纤维素酶高的突变菌,并对其产酶发酵条件进行优化。通过单因素实验研究发酵时间、硫酸铵浓度、微晶纤维素浓度、接种量及搅拌速度等对里氏木霉产酶的影响。在单因素的基础上,通过正交实验对里氏木霉产酶的工艺参数进行优化。结果表明,在诱变时间240s条件下筛选到1株突变里氏木霉ATR-4,其滤纸酶活(FPU)最高可达2.01U·mL^-1。对突变里氏木霉菌株ATR-4的发酵条件优化,筛选得到最佳产酶培养条件为:发酵时间78h,硫酸铵浓度1g·L^-1,接种量10%,搅拌速度400r·min^-1。在此条件下进行验证实验,最高酶活可达4.57U·mL^-1。本研究结果表明,常压室温等离子体(ARTP)诱变可有效对里氏木霉进行诱变育种,改善其产酶能力。

This experiment was conducted to study the mutagenesis breeding and optimal fermentation condition optimization of high yield cellulase enzyme of Trichoderma reesei.Mutants of Trichoderma reesei induced by atmospheric and room temperature plasma(ARTP)were screened for cellulase production.The fermentation conditions of cellulase enzyme production were studied.Five factors including fermentation time,ammonium sulfate concentration,microcrystalline cellulose concentration,inoculation amounts and stirring speed were studied for their effect on the yield of cellulase enzyme.On the base of the single factor experiments,the optimal fermentation conditions for the cellulase production were obtained by orthogonal experiments.The results showed that the optimum parameters for cellulase production were:fermentation time 78 h,ammonium sulfate concentration 1 g·L^-1,inoculation amounts 10%,stirring speed 400 r·min^-1.The cellulase activity was 4.57 U·mL^-1.This study showed that the mutagenesis of atmospheric and room temperature plasma(ARTP)was effective in mutagenesis breeding of Trichoderma reesei,thus to improve enzyme producing ability.